By "Temperatura intel i3 540 3.06GHz. a 90ºC", we understand your system's having an overheating problem. We confirm anything below 72.6°C is fine; this is indicated here, under the "Package Specifications" section. Thus, if the temperature is either reaching or surpassing 72.6°C, to begin troubleshooting, I'd recommend the following:
1. Remove and install the latest temperature monitoring software you are running from within the Operating System.
2. Just to be 100% sure, ensure the heatsink/fan is properly seated.
3. See to it that your board's got the latest BIOS. For this, please, check with the board manufacturer.
Note: The forum support is only provided in English. Hence, as you reply, please, do so in English.
Salem! Before writing this question, I have done all that you say.
My motherboard has updated the BIOS, I tried several software to measure temperature(updated) and thermal paste is fine.
The Intel support center tells me try a different motherboard (I have no access to another motherboard).
In the RMA seller where I bought the processor, said that to prove I have to give them the processor for 1 week or more. That's impossible because I use the PC every day.
I've tried everything in my power.